Drill steel centralizer



June '6, 1944. c, w -ls 2,350;66d

DRILL STEEL CENTRALI ZER Filed 001;. 22, 194,2

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Y raw-4 w Patented June 6, 1944 D-RILLSTEEL CENTRA'LIZER John C. Curtis, Claremont, N. H., assignor to Sullivan 'Machinery Company, a corporation of Massachusetts Application .octoberfzz, 1942, Serial No. 462,931

18 Claims.

This invention relates to rock .drills, and .more' particularly to a centralizer for the drill steel of a rock drill of the mounted type.

In rock drills of the mounted type the drillingmotor which percussively actuates the drill steel is usually mounted on a guide suitably supported" with respect to the work. There is usually provided at the forward end of the guide a centralizer for centering the drill steel during starting or spotting of adrill hole. As the drilling motor is fed along the guide-.guideways and approaches the drillsteel centralizer, the centralizer is usually automatically released from the steeland moved into its non-guiding position so that the drilling motor may be fed along the guide-guideways forwardly past the centralizer. In such drills, it. is also desirable to effect automatic releaseoi-the drill steel centralizer-as the drilling motor is fed rearwardly subsequently to the starting of a drill hole with a relatively short starting steel,.so that as the drill bit which .is of larger diameter than the drill steelloody approaches a centralizer, the latter is automatically moved out of guiding relation with itsdrill steel, thereby'to permit the drill bit to move rearwardly past thesame. Thus in such rock drills, it is desirable'to efiect automatic movement of the .drill steel centralizer into its released non-guiding position duringeither forward or rearward movementof thedrillingtoolalong the guideways of its guide.

It is accordingly an object of the present invention to-providea novel-drill steel centralizer which embodies the desired characteristics as above outlined in that not only isthe-centr'alizer automatically movedinto released-position during forward feed of the drilling tool, but is also antomatically moved into its released positionduring reverse feedof thezdrilling tool. Anotherobject is to provide an improveddrill centralizer having novel means for-effecting automatic. re-. lease of the same .as the drilling to'ol is fed along its .guide. A further object is to provide .anim-z proved drill steel centralizer.havingnovelmounting means .for the centralizer elements thereof; Still anotherobject is to provide an improved drill steel centralizer which is automatically-moved in-' to its released non-guiding position upon bodily movement of the centralizer elements thereof in a direction opposite to that in which the drilling-tool is being fed and having novel releasin means-for the centralizer elements actuateddirectly loy engagement therewith of a part-.of the drilling tool. Still another object is to provide .an improved drill steel centralizer wherein thezdrilling 12001 as his fed forwardly ,along the .guide-:

guideways eliects, through novel operating means, bodily movement of th centralizer elements in a rearward direction, thereby to effect automatic release of the centralizer as the drilling tool approaches the same. A still further object is to provide an improved drill steel centralizer which is automatically released from its steel guiding position directly by engagement with the drill bit therewith as the drilling tool is fed rearwardly along its guide. With these and other objects in view, this invention relates to novel featuresof construction, operation and arrangement of parts, one embodiment of which is given in the specification and illustrated in the accompanying drawins, wherein: c

Fig. 1 is a side elevational view of the forward portion of a rock drill with which can illustrative embodimentof the improved drill steel centralizer is associated.

Fig. 2 is a front end elevational view of the rock drill andsteel' centralizer shown in Fig. l, with the'drill steel'shown in cross section.

Fig. 3 is a view in longitudinal vertical sectiontaken substantially on line 33 of Fig. 2.

Fig. 4 is a cross sectional view taken substantially on line 4-4 of Fig. 1, showing the .centralizer arms in steel guiding'position.

Fig. 5 is a cross sectional View taken substantially on line -5'5-of Fig 1, showing the steel centralizer arms in released non-guiding position.

Fig. 6 is a cross sectional view taken substantially on line 66 of Fig. 3.

In this illustrative embodimentof the invention 'theimproved drill steelcentralizer, generally designated I, is shown associated with a conventional rock drill of the mounted drifter type. It will be evident, however, that the improved centralizer may be associated with other types of rock drills; as for instance, a wagon drill.

The rock drill disclosed herein comprises a conventionaldrilling tool embodying ai drilling motor 2 mounted on a usual guide 3f0r movement toward and from the work. .The drilling motor is of the wellknown pressure fluid actuated hammer type having a motor cylinder 4 containing a reciprocablehammer piston (not shown) for percussively actuating. the:drill-steel 5 .suitably attached in a usual chuck within a frontichuck housing 6 in turn; suitably secured to'the front end of the motor cylinder. The :drill steel 5 carries a1;i ts front end a;;usual,fdetacha.ble.drill bit- 1. The motor-cylinder has; usual glateral guides 8;sli dinglyreceived,iinlongitudinal guidewaysza of the 3 guide 3. Thedrilling .tool :maybe fed=in a well Now referring to the improved drill steel centralizer I, it will be observed that attached by' bolts l2, herein preferably three in number, to the front end of the guide 3 are parallel front and rear transverse'plates I3Iand l4. held in proper spaced relation by spacing sleeves l5' surrounding the bolts between the plates. The rear plate 14 has an integral bearing'boss I6 in which a front bearing portion ll of the feed screw I0 is journaled as shown in Fig, 3. Pivotally mounted on the spacing sleevesof theupper pair of bolts between the plates is a pair of. cooperating centralizerv arms l-8, l8each having an appropriately shaped guidingportion I9 for. engaging the body of the. drill steel .5. The guiding portions of the centralizer arms when the latter are in their closed position, as shown in Fig. 4, embrace the body of the drill steel to hold the latter centered duringstarting or .spotting of-a drill hole in a manner well known to thosev skilled in the art. As shown in the drawing, thecentralizer arms.

are also mounted on. the upper pair of.spacing. sleeves .for bodily, herein translatory, sliding. movement relative thereto in a longitudinal di-,,

rection between the .plates, andthe arms vhave neartheir pivots downwardly projecting lockings lugs engageable when the arms are.in,their foremost guiding position, with opposite vertical side surfaces 2| on the front plate.l3. A torsion spring. 22, common tobothcentralizer arms,-

has coil portions23- encirclingthe upper space ing sleeves at the. armpivots, andthese. coil portions are arranged between the rearsurfaceof the arm hubs and the front face of the rearplate and serve to urge ,the arms forwardly against the front plate.. Thecoil portionsare connected together. by a cross portion 24 extending between the arms, and the endportions, of the springare attached at 25 to the inner sides of the arms.

This torsion spring not only urges the centralizer arms forwardly into their locked position against the front plate I3 with the locking lugs 20 in en: gagement with the vertical side surfaces 2l, but also serves automatically to move the centralizer arms about their pivots when the locking means is released. The lockinglugs 20 on the arms, as the latter are swung apart .into, the position shown in Fig. 5, engage abutment surfaces 26.011. the front plate, thereby to limit outward swing-. ing of the arms.

In the novel constructionfor ,elfectingrearward bodily movement of the centralizer arms into a position to release. the locking lugs 20 from engagement with the. front plate surfaces 2!, there is provided a lever 21 pivoted at 28 on.

the forward end of the guide 3 in adjacency to the rear plate l4, and this lever extends through openings 29 and 30 .in the guide 3 and rear plate I4 respectively, as shown in Fig. 3. This lever has at its rear end a yoke-shaped-actuating portion 3! which straddles the feed screw 10 (Fig.

6). The forward end of this lever has a camportion- 32 engageablewithpins 33 fixed tothe- 7 surface of the cam engaging the arm pins 33 guide-'guideways toward the centralizer.

arm lugs 20. The chuck housing 6 of the drill-; 75..

moves the centralizer arms bodily rearwardly toward the rear plate, thereby automatically to re-' lease the arm locking means from the front plate [3 as the drilling tool is fed forwardly along the The drill bit I has a rear abutment surface 36 engageable with the guiding portions IQ of the centralizer arms so that when the drilling tool is fed rearwardly along the guide-guideways, the arms are moved bodily rearwardly out of locking engagement with the front plate I3. When the locking means is released the torsion spring 22' I8 may be manually swung about their pivots into their guiding position shownin Figs. land 2 with the guidingportions l9.in engagement with the body of the drill steel and at that time, the arms are held locked in guiding position by engagement of the arm lugs 20 with the. side surfaces 2| of the front plate l3. As the drilling tool is fed forwardly along the guide-guideways, the depending lugs 34 on the chuck. housing engage the arms of theyoke .3l of. thelever 21, thereby. swinging the lever about its pivot into the. position indicated in dotted. lines in Fig. 1 to raise the cam portion 32 which engages the arm pins 33, to move the arms bodily rearwardly, thereby to effect release of;'the locking lugs from the front plate surfaces. When the arms are unlocked from the front plate, the. torsion spring acts automatically tov throw the.

centralizer, arms into the wide open non-guiding It is accordingly evident that irrespective of the direction of movement of the drilling tool along the guide-guideways, the centralizer is automatically released from the drill steel,'therby= to prevent accidental engagement of th'e'chu'ck' housing or the drill bit with the centralizer'arm's when the. latter are held closed which might result in damage to the drill. When-the centralizer arms are. intheir wide open position shown in. Fig. 5 and it is desired to positionthe guidearms in guiding relation with the drill steel, the operator may manually 'swing'thearms When it. is desired to start or spot a drill hole the centralizer arms against the tension of the torsion spring 22 into engagement with the drillsteel and thereafter may shove the guide arms-bodily forwardly into locking engagement with the frontl'plate I3. When the centralizer arms are moved into their closed guiding position, the pins 33 thereon are brought into operativerelation with respect to the cam portion of the operating lever 21.

As a result of thisinvention, it will be noted that an improved drill steel centralizer is provided which is automatically moved into its released non-guiding position and the drilling tool assumes predetermined, positions asit is fed either forwardly or rearwardly along the guideways of its guide. It will further be evident that by mounting the centralizer arms so that they move rearwardly out of their locked position, the centralizer may be automatically released from the drill steel by engagement of the drill bit with the guide arms. It will further be evident that by the provision of the improved operating means the centralizer arms are automatically moved into their released non-guiding position in an extremely effective manner. Other uses and. advantages of the improved drill steel centralizer will be clearly apparent to those skilled in the art.

While there is in this application specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a drill steel centralizer, a support, centralizer means mounted on said support to move translationally relative thereto into and out of steel guiding position, and means movably mounted on said support and engaging said centralizer means for effecting rearward translatory movement of the latter with respect to the drill steel out of steel guiding position.

2. In a drill steel centralizer, a support, a pair of relatively movable, swingable centralizer arms mounted on said support for translatory movement into and out of steel guiding position, and means movably mounted on said support and engageable with said arms for effecting rearward translatory movement of the latter with respect to the drill steel into a position to permit relative swinging of said arms out of steel guiding position.

3. In a rock drill, a guide providing guideways, a drilling tool for actuating a drill steel and movable back and forth along said guide-guideways, a drill steel centralizer mounted on said guide for centering the drill steel, and means automatically operative as said drilling tool moves rearwardly along said guide-guideways for effecting release of said centralizer from the steel.

4. In a rock drill, a guide providing guideways, a drilling motor for actuating a drill steel and movable back and forth along said guide-guideways, a drill steel centralizer mounted on said guide for centering the drill steel and including centralizer means mounted for translatory movement into and out of steel engaging position, and means operated by said drilling motor as the latter moves forwardly along said guide for effecting rearward translatory movement of said centralizer means toward its released posi tion. 1 5. In a drill steel centralizer, a support, drill steelcentralizer means mounted on'said supportand movable translationally relative theretotoward its released position, and a lever on said support for translationally moving said centralizer 'means toward released position.

6. In arock drill, a guide, a drilling tool for actuating a drill steel and movable'back and forth along said guide, a drill steel centralizer on said guide for centering the drill steel, and means for effecting automatic release of said centralizer from said steel when said drilling tool assumes a predetermined position on said guide during movement thereof in one .direction along said guide and also when said drilling tool assumes 'a predetermined position during the opposite movement thereof. I

'7.'In a rock drill, a guide, a drillingmotor for actuating a drill steel and movable forwardly along said guide toward thework, a.drill steel centralizer-mounted on said guide for centering the drill steel, said centralizer including; 'centralizer means movable rearwardly with respect to said guide towards its released non-guiding position, and means operated by said motor as it approaches said centralizer for effecting rearward movement of said centralizer means.

8. In adrill steel centralizer, a'support, a pair of centralizer arms mounted on said support for pivotal and translatori movements and having 7 steel engaging portions, and means on said's'up port and engaging said arms near their pivots at the sides of the latter remote from saidsteel engaging portions for effecting translatory movement thereof.

9. In a drill steel centralizer, a support, a pair of relatively movable centralizer arms mounted on said support for translatory and pivotal movements, locking means for holding said arms against pivotal movement and releasable upon translatory movement of said arms into a predetermined position, and lever mechanism on said support for translationally moving said arms.

10. In a drill steel centralizer, a support, a pair of centralizer arms mounted on said support for pivotal and translatory movements and having steel engaging portions, locking means for holding said arms against pivotal movement and releasable upon a predetermined translatory movement of said arms, and means on said support operatively engageable with said arms near the pivotal axes thereof at the sides of said pivotal axes remote from said steel engaging portions for translationally moving said arms.

11. In a rock drill, a guide, a drilling tool for actuating a drill steel and movable along said guide, a drill steel centralizer mounted on said guide for centering the drill steel, said centralizer embodying a locking element movable rearwardly to effect release of said centralizer from the drill steel, and means operated by said drilling tool as the latter moves forwardly along said guide for effecting rearward movement of said locking element.

12. In a rock drill, a guide, a drilling tool for actuating a drill steel which carries a drill bit, said tool being movable back and forth along said guide, a drill steel centralizer on said guide for centering the drill steel, and means for looking said centralizer in guiding position and automatically releasable upon engagement of said dri1l bit:therewith as. said drilling tool moyes rearwardly along said guide.

l .13. In a rock drill, a supportadapted tolsupport a, drilling tool for .feedingmovement, therealong, centralizer means mounted on said support to move translationally relative thereto into and out. of. tool guiding position, and ,meansactuatediby thedrilling tool for effecting translae toryr movement of .said centralizermeans, said last mentioned means including an operating member mounted on said support for movement relative thereto and to said. centralizer means, said operating membermoving said centralizer means translationally and having a portion projecting into the path of tool movement.

-14; In a rockdrill, a support adapted to support adrill steel actuator for movement there.- a1ong,.centra1izeitmeans mounted on said support to move translationally relative thereto intoand out of steel guidingposition, and means mounted on said support for movement with respect tothe drill .steel actuator andto said centralizermeans for translationally moving said centralizer means. V V

i .15. InfarockdrilLa support adapted to support a drill. steel actuator for movement therealong, centralizer means mounted ,on said support to move translationally relative thereto into and'out, of steel guiding position, and means mounted on said support for movement witherespect to said steel actuator andsaid centralizer means and engaging said .centralizer means at points remote from the steel engaging portions thereof for translationally moving said centralertm I 2,345.0,eoo

16. In a drill steel centralizer; a support, centralizer means mounted on said support to move into and ;out of steel guiding position, means ior lockingysaid'centralizer means in' steel guidingjposition, ,andmeans movably mounted on said support and; engaging said centralizer means for effecting rearward translatory movement of said centralizer means relative to said support toeffectrelease of said locking means.

.,17, In a roclg drill, a guide along which a drill steel actuatorisuguided .for movement, centralizer; meansmounted at the front end of said guide to move into andout of steel guiding position, means for locking said centralizer means in steel guiding position, and means movably mounted on said guideand having a portion projecting into the path of movement of said steel'actuator for actuation by the latter, said last mentioned means upon actuation thereof effecting rearward translatory movement of said centralizer means relative to said guide to effect release of said locking means.

' 18. In a drill steel centralizer, a support, a pair of guide .arms pivotally mounted on said support to swing relative thereto about spaced apart parallel axes, said arms being movable translationally relative to said support during their movement out of their steel guiding position, and-anactuator element movably mounted on said support and projecting into the space between the arm pivot axes for translationally moving said arms.

JOHN C. CURTIS. 

